=When the worm is ready to spin, she throws out two tiny little threads one from each side of her head.= This is a secretion and is a kind of jellylike fluid. As the air touches it, it hardens. She works her head back and forth, and the tiny filaments, or threads, as they are called, are joined together into one. She works and works until she has built a house of silk threads all glued together so that it seems like a mass of parchment paper. These houses are about 1½-inches in length, and are white or yellow in color. In China and Japan these cocoons are grown and tended very carefully. The outside of the cocoon is covered with the loose fluffy silk which the worm uses to attach his home to a leaf or twig. It takes the worm three weeks to make this long, continuous thread called a cocoon. During that time a wonderful thing happens. The worm inside the cocoon is changed to a moth like her mother and father and is ready to leave her home by eating her way out. What would happen to the long silk thread if she did that? Yes, it would be broken into small pieces and not be one continuous piece. Some moths are permitted to come out (see Fig. 65). They then find a mate and soon more tiny eggs are laid by the mother moth; and all the story begins again. =A sad thing happens when cocoons are grown for the silk.= The moths are not allowed to come out and break the thread; but are put in a very hot place so they die inside. The cocoons are then ready to be reeled or wound off. They are placed in basins of hot water because the gummy secretion of the worm must be softened. The ends from four or five cocoons are caught together and reeled, or wound, off together. This makes a strand of raw silk. [Illustration: _Courtesy of Corticelli Silk Co. Copyright, 1895, by Nonotuck Silk Co._ FIG. 65.--Corticelli cocoons from which the moths have emerged.] John Alden told the following story. He said his father read it aloud the night before when the family gathered about the big open fire. Once upon a time, long ago, people did not know how to use the beautiful fibers of the silkworm. We are told that a Chinese empress discovered how to use it as long ago as 2700 years before the birth of Christ. Every year, in April, the Chinese people have a celebration in her honor, because of her valuable discovery. Think of all the riches she added to her country because of this secret. It is said that for many years this secret was kept; but later some monks traveling east to India and Constantinople told others how to reel the silk fiber. Then the use of silk fiber spread to Greece and Italy and Spain, and by the fourteenth century was common in France. Since then, silk manufacture has grown rapidly in importance. John traced the journey on the map. Will you see if you can trace this journey of silk manufacture. Where do you think the secret was carried from France? [Illustration: _Courtesy of United States Department of Agriculture._